Hydrojet Pro

[Bill D]

Lies! Or maybe they're not... I don't know what to believe. I like how our members are there to state some facts.

It's a bold strategy, let's see how it plays out.

 

[Bruce]

It is strange that "boat rookie" would choose to launch his product on a "third world" forum.

 

[Cobra Jet Steering LLC]

I don't think they understand the doctrine of equivalents or that a patent pending status provides you no protection on infringements, I already see what I believe is one obvious infringement jet boat pilot can file. The listing on e bay is quite humorous also.
I guess I should send this to my people just for grins.
I really have a hard time taking this product serious though and I firmly believe the original poster is actually a POSER . But who cares.

 

[JetBoatPilot]

I find it amusing that they even copied he shape of our TV XL fin and then modified it thinking that might protect them.

We'll see what out attorneys say. Our patent was just issued and we have them working alot these days.

 

[jlcj7]

I was waiting to see what you would say

 

[Gym]

You guys, @Cobra Jet Steering LLC & @JetBoatPilot obviously missed an untapped market... The ignorant and uninformed.

 

[davel501]

I think it is interesting that these do not work in the way we would expect them to. They come up as soon as you push the throttles forward (they are tied to the buckets). Most people assumption (mine included) of the fins working like rudders in incorrect. The fins really elongate the jets . @Cobra Jet Steering LLC was a bit ahead of me on this one I think. He mentions how the fangs force the thrust forward in reverse in the instructions and @JetBoatPilot actually put thrust vectoring in the name of their product. These new fins are an interesting new way to solve the problem. It is up to the consumer to decide what is best for themselves. We had Ford, then Chevy and now we have Chrysler.

 

[Bruce]

Here is the installation video

 

[Julian]

Cobra fins and thrust vectors both work the same way this new fin works with one exception.

In reverse they are identical, they:

1. direct the flow of water from the jet output
2. use their surface area like a rudder

In forward cobra fins and thrust vectors only act as a rudder because the jet output (thrust vectoring) doesn't benefit from two fins on each side of it. This is why these fins have gotten larger and larger over time....to increase the surface area of the rudder. This new model has no, or limited rudder effect when the buckets are in the forward position, and having side "braces" to the jet output seems pointless to me as there is nothing in the way of the thrust from the jet like there is in reverse.

Perhaps I'm missing something, but these look like they will only solve half the problem and are more expensive.....but I'm happy to be proven wrong....lets see some real world turning video!

 

[swatski]

I think it is interesting that these do not work in the way we would expect them to. They come up as soon as you push the throttles forward (they are tied to the buckets). Most people assumption (mine included) of the fins working like rudders in incorrect. The fins really elongate the jets .

Your assumption is correct. And trust vectoring and rudder effects are not mutually exclusive.

The Ultimates certainly do work like rudders at speed. When installed in a manner that makes them stay down at speed. That is the whole point, really.

On the other hand, the "new" knockoff hydro-whatever work EXACTLY THE SAME as the older Cobras and all TVs, they gradually come up at speed, be that by being pulled by the gate or being forced up by the jet stream pushing an actuator.

 

[davel501]

Your assumption is correct. And trust vectoring and rudder effects are not mutually exclusive.

The Ultimates certainly do work like rudders at speed. When installed in a manner that makes them stay down at speed. That is the whole point, really.

On the other hand, the "new" knockoff hydro-whatever work EXACTLY THE SAME as the older Cobras and all TVs, they gradually come up at speed, be that by being pulled by the gate or being forced up by the jet stream pushing an actuator.

They don't though. Go to their home page and watch the gif in the lower right corner. They come up when you put the throttle forward. Completely kills the no-wake and idle forward use cases. You really only get reverse assist from these and then thrust vectoring.

 

[swatski]

Cobra fins and thrust vectors both work the same way this new fin works with one exception.

In reverse they are identical, they:

1. direct the flow of water from the jet output
2. use their surface area like a rudder

In forward cobra fins and thrust vectors only act as a rudder because the jet output (thrust vectoring) doesn't benefit from two fins on each side of it. This is why these fins have gotten larger and larger over time....to increase the surface area of the rudder. This new model has no, or limited rudder effect when the buckets are in the forward position, and having side "braces" to the jet output seems pointless to me as there is nothing in the way of the thrust from the jet like there is in reverse.

Perhaps I'm missing something, but these look like they will only solve half the problem and are more expensive.....but I'm happy to be proven wrong....lets see some real world turning video!

@Julian I have to say you have me pretty confused. Maybe it is the same as with the fangs, where there was some initial confusion about what do they look like...

I don't see these new hydrojets being fundamentally different than older Cobras or TVs.

 

[swatski]

They don't though. Go to their home page and watch the gif in the lower right corner. They come up when you put the throttle forward. Completely kills the no-wake and idle forward use cases. You really only get reverse assist from these and then thrust vectoring.

That would be correct only if you lift the gate all the way up in one instant, which is usually not the case. At slow speeds and in no-wake mode the gate is partially lowered and so are the hydrojet fins.
But even with the gate fully up, you still have these little "ears" hanging down just enough to have some influence (perhaps), as in the gif.
Different means of lifting the fins, but it is the same concept.

 

[davel501]

That would be correct only if you lift the gate all the way up in one instant, which is usually not the case. At slow speeds and in no-wake mode the gate is partially lowered and so are the hydrojet fins.
But even with the gate fully up, you still have these little "ears" hanging down just enough to have some influence (perhaps), as in the gif.
Different means of lifting the fins, but it is the same concept.

This is my 2010 242 LS with the throttles forward to the first detent like you would have them set for no wake areas or leaving the dock.

 

[Julian]

And here is where their fins sit when you are in forward....


Looks to me like barely 1/4 inch of the fin is below the pump in the water flow under the boat where a rudder would have an impact. Being to the sides of the jet output would seem to me to have no effect at all on steering....

 

[swatski]

This is my 2010 242 LS with the throttles forward to the first detent like you would have them set for no wake areas or leaving the dock.

View attachment 38132

That looks like the gate is fully up in your picture. Not sure how would the 'no-wake" mode work with a gate fully up/open?
I am not looking at mine right now, but if I recall correctly, mine will open gradually with the throttle.

I also don't know what speed it takes to lift up the Cobras or TVs. But, the bottom line is - no matter how you slice it all three systems come up at speed. The new one is pulled by the gate, the other two are lifted by water pressure on the actuators. They all come up, albeit perhaps at different speeds

I have ZERO interest arguing my point. But I think this is pretty simple.

 

[Julian]

Not an arguement at all....a discussion of the mechanics.

The gates on our boat move to the forward or the reverse position BEFORE any throttle is applied. So if you are in any level of no wake mode, the gate is fully open. The TVs and Cobras allow you to have the fins below the pump while running forward in no wake mode. This new design does not. Thats all I'm pointing out. So they will only work in reverse.

 

[davel501]

Not an arguement at all....a discussion of the mechanics.

The gates on our boat move to the forward or the reverse position BEFORE any throttle is applied. So if you are in any level of no wake mode, the gate is fully open. The TVs and Cobras allow you to have the fins below the pump while running forward in no wake mode. This new design does not. Thats all I'm pointing out. So they will only work in reverse.

This.

 

[davel501]

Can the thrust vectors be locked down so they do not come up at speed or is that just a cobra thing? I do a lot of shallow water boating so I would never lock mine down but I know I have the option with the cobras.

 

[swatski]

This.

I always thought the TDE and the no-wake mode operated using partial forward or reverse shift/reverse gate positioning, in addition to operating throttle/RPM. But if the gate goes all the way up BEFORE throttle opens up/RPM rise, than I had it wrong.
I think I stand corrected.

EDIT: Are you guys sure the shift/reverse gate goes ALL THE WAY UP with throttle in FIRST detent?

EDIT: I guess I do not stand corrected, see @haknslash post below.